Prosecutors said the victim is among the 12 children he is already accused of molesting in Los Angeles County from 2004 to 2012, said Jane Robison, a district attorney's spokeswoman.

The bulk of the allegations involve abuse between September 2011 and March 2012. LAPD began investigating Pimentel in March 2012 after reports from parents at George de la Torre Jr. Elementary in Wilmington.

Several years ago, Newport Beach police investigated allegations involving four victims, but the Orange County district attorney's office declined to file criminal charges and ordered a reinvestigation. That work was recently turned over to prosecutors in Los Angeles County.

Pimentel has pleaded not guilty and his lawyer told reporters the charges were allegations

But a law enforcement source close to the investigation said Pimentel has been accused of touching children "multiple times over a period of time."

The source, who spoke on the condition of anonymity because the case was ongoing, said Pimentel is accused of inappropriately touching 9- and 10-year-old girls.